Physics Lecture: Potential Energy and Energy Conservation

These flashcards cover essential concepts related to potential energy, gravitational force, conservation of energy, and the work-energy principle.

Potential Energy

Energy possessed by an object due to its position relative to other objects, stresses within itself, its electric charge, and other factors.

Conservation of Mechanical Energy

In a closed system, the total mechanical energy (kinetic + potential energy) remains constant if only conservative forces are acting.

Gravitational Force

The force of attraction between two masses; on Earth, it is approximately 9.81 m/s².

Reference Plane

A flat surface used for comparison of height; at this level, potential energy is often defined as zero.

Work Done by Gravity

The work done by the gravitational force when an object moves vertically, dependent only on the height difference between two points.

Non-Conservative Forces

Forces whose work depends on the path taken; they dissipate mechanical energy as heat or sound, such as friction.

Kinetic Energy

Energy that a body possesses due to its motion, calculated as 1/2mv², where m is mass and v is velocity.

Conservative Forces

Forces that do not dissipate energy and whose work is independent of the path taken between two points.

Mechanical Energy

The sum of potential and kinetic energy in a system.

Height Measurement

A measurement of how far above a reference point an object is located, affecting its potential energy.

Energy Transformation

The process of changing energy from one form to another, such as gravitational potential energy transforming into kinetic energy.

Path Independence

The principle that the work done by a conservative force is dependent only on the initial and final positions, not the path taken.

Work-Energy Principle

The principle stating that the work done on an object results in a change in its kinetic energy.

Negative Work

Work done against the motion of an object; for gravitational work, it means that the force acts to reduce the object's energy.